Water Quality Analysis of Mountain Water Supply at Nanglae Nai Village, Nanglae Subdistrict, Muang District, Chiang Rai Province

Abstract

This research aimed to analyze water quality on physical, chemical and biological parameters of mountain tap water in Nanglae Nai village in comparison to Drinking Water Quality Criteria of Department of Health, 2010. Water samples were collected three times in March, June and July 2016 at 6 sampling sites.  It was found that the physical parameters, including turbidity and pH were between 3.13 ± 1.83 – 8.32 ± 9.75 NTU and 7.69 ± 0.61– 7.82 ± 0.81, respectively. The pH of tap water from all sampling sites did not exceed the standard level while turbidity value was higher than the standard level. The chemical parameters including hardness, fluoride, manganese, iron and nitrate nitrogen were between 47.00 ± 16.52 – 53.00 ± 6.28 mg/L, 0.36 ± 0.18 – 0.62 ± 0.24 mg/L, 0.50 ± 0.27 – 0.80 ± 0.42 mg/L, 0.04 ± 0.03 – 0.11 ± 0.05 mg/L and 0.40 ± 0.10 – 0.70 ± 0.31   mg/L, respectively. All the chemical parameters, except manganese content, of tap water from all sampling sites did not exceed the standard level.  Furthermore, the biological assessment was conducted and founded that quantities of total coliform bacteria and fecal coliform bacteria were 2.2 – >23 MPN/100 ml and 1.1 – >23 MPN/100 ml, respectively.  Both parameter values failed to meet the quality standard of Drinking Water Quality Criteria of Department of Health, 2010.  Therefore, the study suggested that mountain tap water of Nanglae Nai village should be filtered and boiled in order to generally kill microorganisms before consumption for health safety.